Re: [Chicken-hackers] The use of the null-pointer and null-pointer? procedures

[Kon Lovett]

On May 11, 2011, at 8:14 AM, Peter Bex wrote:

> On Wed, May 11, 2011 at 08:21:32AM -0400, Felix wrote:
> > > On Wed, May 11, 2011 at 05:25:12AM -0400, Felix wrote:
> > > > > I was wondering what use does (null-pointer?) has.
> > > >
> > > > Historical. I will deprecate.
> > >
> > > Thanks, Felix.  I noticed the documentation says
> > > "Another way to say (address->pointer 0)".  Should the address- 
> > > >pointer
> > > procedure return #f when given 0?
> >
> > No, otherwise you couldn't create a pointer object containing a NULL
> > pointer... :-) I think we can expect a user to be able to code this.
>
> I understand that this wouldn't be possible. But what is the reason
> this has to be possible, considering null pointers are represented
> as #f everywhere else?  For consistency it would make sense to return
> #f here too, but of course you could also argue that it would be more
> consistent to always return a pointer...

Possible to apply the #f representation for NULL across all pointer  
procedures but is this really the problem? The original issue was  
brought on by the lack of instructive examples in the manual for FFI  
use.

Suggest leaving lolevel alone and add to the FFI documentation instead.

> Ah well
>
> Cheers,
> Peter
> --
> http://sjamaan.ath.cx
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